Dissolved and entrained air in fluid pumped by a positive displacement pump reduces a pump's output flow capacity resulting in reduced output pressure and unwanted noise due to cavitation. Cavitation occurs when the entrained air collapses or implodes as it passes from a relatively low pressure region of a pump, such as a fluid inlet, to a relatively higher pressure region, such as a discharge or outlet region. The presence of cavitation in a pump has the potential of severely limiting its high speed output flow capability.